JP4858744B2 - Exposure equipment - Google Patents

Description

  The present invention relates to an exposure apparatus, and more particularly to an exposure apparatus that exposes a substrate in a lithography process for manufacturing an electronic device such as a semiconductor element (such as an integrated circuit) or a liquid crystal display element.

  Conventionally, in a lithography process for manufacturing an electronic device such as a semiconductor element (such as an integrated circuit) or a liquid crystal display element, a pattern of a mask or a reticle (hereinafter, collectively referred to as “reticle”) is transferred through a projection optical system to a resist ( Step-and-repeat reduction projection exposure apparatus (so-called so-called “photosensitive agent”) is transferred to each of a plurality of shot areas on a photosensitive substrate (hereinafter referred to as “wafer”) such as a wafer or a glass plate. Stepper) and step-and-scan type projection exposure apparatus (so-called scanning stepper (also called a scanner)) are mainly used.

  In this type of exposure apparatus, a linear motor or the like is used as a drive mechanism for driving a stage that holds and moves a reticle or wafer. In the linear motor or the like, current is supplied to the coil, so that the coil generates heat, The measurement accuracy of an interferometer or the like that measures the position of the stage may be deteriorated due to the influence of the heat generation. For this reason, it is necessary to cool a linear motor or the like, and in recent years, for example, a fluorine-based inert liquid whose temperature is controlled by a temperature control device, for example, is supplied as a refrigerant to a heat generating part such as a linear motor. It was done.

  Recently, however, fluorine-based inert liquids have (1) a very high unit price of refrigerant, (2) a high global warming potential, and (3) a heat capacity (specific heat x density) per unit volume of water. In consideration of the fact that it is as small as about 1/2 of the above, it is considered to use water (pure water) having a large heat capacity as the refrigerant (see, for example, Patent Document 1).

JP 2003-22955 A

From the first viewpoint, the present invention provides a projection optical system (PL) for projecting a pattern onto a substrate (W), and a resinous supply pipe between the projection optical system (PL) and the substrate (W). An exposure apparatus main body (10A) including a liquid supply apparatus (5) for supplying liquid via (77); and a first supply path (28) for supplying water to a drive device (86) in the exposure apparatus main body. And an ion removing device (51) for removing at least part of the water supplied to the driving device through the first supply path and removing ions from the passing water ; upstream of the driving device Or a second supply path (28d) branched from the first supply path on the downstream side and supplying a part of the water flowing in the first supply path to a portion different from the drive device of the exposure apparatus body; The projection optical system and the substrate are connected via the resin supply pipe (77). An exposure apparatus characterized by comprising; the liquid supplied to a first temperature controller for temperature control by heat exchange with the water supplied from the second supply path.

  According to this, it becomes possible to control the temperature of the drive device in the exposure apparatus, which is different from the drive device, with water from which ions have been removed.

  In order to explain the present invention in an easy-to-understand manner, the description has been made in association with the reference numerals of the drawings representing one embodiment, but it goes without saying that the present invention is not limited to the embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a schematic plan view of a substrate processing system according to an embodiment including an exposure apparatus according to the present invention.

  The substrate processing system 100 of FIG. 1 is installed in a clean room having a cleanliness class of about 100 to 1000. The substrate processing system 100 includes an exposure apparatus 10 and a coater / developer (hereinafter referred to as “C / D”) arranged on the floor F of a clean room with a predetermined interval in the X-axis direction (left and right direction in FIG. 1). And an interface unit 14 for connecting the exposure apparatus 10 and the C / D 12 in-line.

  As shown in FIG. 1, the exposure apparatus 10 includes a loader chamber 130 and a main body chamber 120. The loader chamber 130 accommodates a wafer transfer system (loader) and the like.

  An exposure apparatus main body 10A shown in FIG. 2 is accommodated in the main body chamber 120, and a deminer 51 (which will be described in more detail later) in proximity to the + X side of the exposure apparatus main body 10A. A shelf 13 for storing an electrical system component called a rear rack is provided.

  As shown in FIG. 2, the exposure apparatus main body 10A includes an illumination system IOP and a reticle illuminated by exposure illumination light (hereinafter referred to as “illumination light” or “exposure light”) IL from the illumination system IOP. Reticle stage RST for holding R, projection unit PU including projection optical system PL for projecting illumination light IL emitted from reticle R onto wafer W as a substrate, wafer stage WST on which wafer W is placed, and exposure stage For example, a wafer stage device 50 including a measurement stage MST used for measurement, and a control system thereof.

  The illumination system IOP is configured in the same manner as the illumination system disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-313250 (corresponding US Patent Application Publication No. 2003/0025890), and is defined by a reticle blind (not shown). A slit-like illumination area IAR elongated in the X-axis direction (the direction orthogonal to the paper surface in FIG. 2) on R is illuminated with illumination light (exposure light) IL with substantially uniform illuminance. Here, as the illumination light IL, for example, ArF excimer laser light (wavelength 193 nm) is used.

  On reticle stage RST, reticle R on which a circuit pattern or the like is formed on its pattern surface (lower surface in FIG. 2) is fixed, for example, by vacuum suction. The reticle stage RST can be finely driven in the XY plane by a reticle stage drive unit 11 (not shown in FIG. 2, see FIG. 6) including a linear motor, for example, and has a predetermined scanning direction (here in FIG. 2). It can be driven at a scanning speed specified in the Y-axis direction, which is the left-right direction in the drawing.

  The position of the reticle stage RST in the stage moving plane (including rotation around the Z axis) is moved by a reticle laser interferometer (hereinafter referred to as “reticle interferometer”) 116 in the moving mirror 15 (actually in the Y axis direction). (A Y movable mirror having a reflecting surface orthogonal to the X moving mirror having a reflecting surface orthogonal to the X-axis direction is provided) and is always detected with a resolution of, for example, about 0.5 to 1 nm. The measurement value of the reticle interferometer 116 is sent to the main controller 20 (not shown in FIG. 2, see FIG. 6). In the main controller 20, the reticle stage drive unit is based on the measurement value of the reticle interferometer 116. 11 is used to control the position (and speed) of reticle stage RST in the X-axis direction, Y-axis direction, and θz direction (rotation direction about the Z-axis).

  The projection unit PU is disposed below the reticle stage RST in FIG. The projection unit PU includes a lens barrel 40 and a projection optical system PL composed of a plurality of optical elements held in the lens barrel 40 in a predetermined positional relationship. As the projection optical system PL, for example, a refractive optical system including a plurality of lenses (lens elements) having a common optical axis AX in the Z-axis direction is used. This projection optical system PL is, for example, both-side telecentric and has a predetermined projection magnification (for example, 1/4 or 1/5). For this reason, when the illumination area IAR on the reticle R is illuminated by the illumination light IL from the illumination system IOP, the illumination light IL that has passed through the reticle R is illuminated via the projection optical system PL (projection unit PU). A reduced image of the circuit pattern of the reticle R in the area IAR (a reduced image of a part of the circuit pattern) is conjugate to the illumination area IAR on the wafer W whose surface is coated with a resist (photosensitive agent) (hereinafter, “ (Also referred to as “exposure area”).

  Further, in the exposure apparatus main body 10A of the present embodiment, in the vicinity of a lens (hereinafter also referred to as “tip lens”) 191 that is an optical element on the most image plane side (wafer W side) constituting the projection optical system PL, A liquid supply nozzle 31A and a liquid recovery nozzle 31B constituting the liquid immersion device 32 are provided.

  Here, as the liquid, ultrapure water (hereinafter simply referred to as “water” unless otherwise required) through which ArF excimer laser light (light having a wavelength of 193 nm) passes is used. Ultrapure water has the advantage that it can be easily obtained in large quantities at a semiconductor manufacturing plant or the like and has no adverse effect on the photoresist, optical lens, etc. on the wafer.

  The refractive index n of water with respect to ArF excimer laser light is approximately 1.44. In this water, the wavelength of the illumination light IL is shortened to 193 nm × 1 / n = about 134 nm.

  The liquid supply nozzle 31A is connected to the liquid supply device 5 (not shown in FIG. 2, see FIG. 6), and the liquid recovery nozzle 31B is connected to the liquid recovery device 6 (not shown in FIG. 2, see FIG. 6). Has been. The liquid supply device 5 and the liquid recovery device 6 are controlled by the main controller 20. The main controller 20 controls the liquid supply device 5 to supply water between the tip lens 191 and the wafer W via the liquid supply nozzle 31A, and controls the liquid recovery device 6 to control the liquid. Water is recovered from between the front lens 191 and the wafer W via the recovery nozzle 31B. Thereby, a fixed amount of water Lq (see FIG. 2) is held between the front lens 191 and the wafer W.

  Even when the measurement stage MST is positioned below the projection unit PU, it is possible to fill water between the measurement table MTB and the front lens 191 in the same manner as described above.

  In the above description, in order to simplify the description, one liquid supply nozzle and one liquid recovery nozzle are provided. However, the present invention is not limited to this, for example, International Publication No. 99/49504. It is good also as employ | adopting the structure which has many nozzles so that it may be disclosed by number pamphlet. In short, as long as the liquid can be supplied between the lowermost optical member (tip lens) 191 constituting the projection optical system PL and the wafer W, any configuration may be used.

  An off-axis alignment system (hereinafter abbreviated as “alignment system”) ALG is provided on the −Y side of the projection unit PU. The alignment system ALG is held by a holding member that holds the projection unit PU. The imaging signal from the alignment system ALG is supplied to the main controller 20 in FIG.

  The wafer stage apparatus 50 includes a base board 112, a wafer stage WST and a measurement stage MST disposed above the upper surface of the base board 112, and an interferometer system 118 that measures the positions of these stages WST and MST (see FIG. 6) and a stage drive unit 124 (see FIG. 6) for driving the stages WST and MST.

  On the bottom surfaces of wafer stage WST and measurement stage MST, non-contact bearings (not shown), for example, air static pressure bearings (that is, air bearings (also referred to as air pads)) are provided at a plurality of locations. The wafer stage WST and the measurement stage MST are levitated and supported above the upper surface of the base plate 112 through a clearance of about several μm by static pressure of pressurized air ejected from the base plate 112 toward the upper surface of the base plate 112. ing. Each stage WST and MST is driven (including θz rotation) independently from each other in the XY plane by the stage driving unit 124.

  More specifically, as shown in FIG. 2, the wafer stage WST includes a wafer stage main body 91 in which the air bearing is provided on the bottom surface, and a Z / leveling mechanism (not shown) on the wafer stage main body 91. (For example, including an actuator such as a voice coil motor) and mounted on the wafer stage main body 91 in the Z-axis direction, the X-axis rotation direction (θx direction), and the Y-axis rotation direction ( and a wafer table WTB that is finely driven in the θy direction).

  On wafer table WTB, a wafer holder (not shown) for holding wafer W by vacuum suction or the like is provided. Further, on the upper surface of wafer table WTB, a substantially rectangular auxiliary plate (liquid repellent plate) 128 having a circular opening with an inner diameter slightly larger than the outer diameter of wafer W placed on the wafer holder at the center is formed. Is provided. The auxiliary plate 128 is set so that the surface thereof is substantially flush with the wafer W attracted and held by the wafer holder.

  The measurement stage MST includes a measurement stage main body 92 provided with the air bearing on the bottom surface thereof, and a measurement table MTB mounted on the measurement stage main body 92 via a Z / leveling mechanism (not shown). .

  Various measurement members are provided on the measurement table MTB (and the measurement stage main body 92). As this measurement member, for example, a reference mark region FM in which a plurality of reference marks disclosed in Japanese Patent Laid-Open No. 5-21314 (corresponding US Pat. No. 5,243,195) is formed, or a projection optical system Sensors (such as an illuminance monitor, an illuminance unevenness sensor, and an aerial image measuring instrument) that receive the illumination light IL via the PL are included.

  In the present embodiment, it is used for the measurement using the illumination light IL corresponding to the immersion exposure in which the wafer W is exposed by the exposure light (illumination light) IL through the projection optical system PL and water. In the illuminance monitor, the illuminance unevenness sensor, and the aerial image measuring instrument, the illumination light IL is received through the projection optical system PL and water. In addition, for example, each sensor may be mounted on the measurement table MTB (and the measurement stage main body 92) only partially, for example, or the entire sensor may be arranged on the measurement table MTB (and the measurement stage main body 92). May be.

  Next, the stage drive unit 124 will be described. As shown in the plan view of FIG. 3, a pair of Y-axis stators 86 and 87 extending in the Y-axis direction are disposed on the −X side and + X side of the base board 112, respectively. These Y-axis stators 86 and 87 are constituted by armature units having a plurality of coils therein. A pair of Y-axis movers 82 and 83 provided respectively at one end and the other end of the X-axis stator 80 extending in the X-axis direction are engaged with the Y-axis stators 86 and 87 in the inserted state. Match. In addition, a pair of Y-axis movers 84 and 85 provided respectively at one end and the other end in the longitudinal direction of the X-axis stator 81 extending in the X-axis direction are inserted into the Y-axis stators 86 and 87, respectively. Is engaged. Each of the Y-axis movers 82, 84, 83, 85 is constituted by a magnetic pole unit having a plurality of permanent magnets.

  That is, a moving magnet type Y-axis linear motor that drives each of the Y-axis movers 82 and 84 in the Y-axis direction by the Y-axis stator 86 and the Y-axis mover 82 and the Y-axis mover 84, respectively. A moving magnet type Y-axis linear motor configured to drive each of the Y-axis movers 83 and 85 in the Y-axis direction by the Y-axis stator 87 and the Y-axis mover 83 and the Y-axis mover 85 is provided. Each is composed. In the following description, each of the four Y-axis linear motors is appropriately designated by using the same reference numerals as those of the Y-axis movers 82, 84, 83, and 85, and the Y-axis linear motor 82, the Y-axis linear motor 84, and the like. These are called a Y-axis linear motor 83 and a Y-axis linear motor 85.

  Of the four Y-axis linear motors, the measurement stage MST is driven in the Y-axis direction integrally with the X-axis linear motor 80 by the two Y-axis linear motors 82 and 83, and the remaining two Y-axis linear motors 84, 85, wafer stage WST is driven in the Y-axis direction integrally with X-axis linear motor 81.

  Each of the X-axis stators 80 and 81 is constituted by an armature unit that incorporates, for example, armature coils arranged at a predetermined interval along the X-axis direction. One X-axis stator 81 is inserted into an opening (not shown) formed in wafer stage main body 91 (not shown in FIG. 3, refer to FIG. 2) constituting wafer stage WST. Inside the opening of the wafer stage main body 91, for example, an X-axis movable element (not shown) composed of a magnetic pole unit is provided. That is, the X-axis stator 81 and the X-axis mover constitute a moving magnet type X-axis linear motor that drives wafer stage WST in the X-axis direction. Hereinafter, this X-axis linear motor will be appropriately referred to as an X-axis linear motor 81 using the same reference numerals as those of the X-axis stator 81 that is the stator.

  The other X-axis stator 80 is inserted into an opening (not shown) formed in a measurement stage main body 92 (not shown in FIG. 3, refer to FIG. 2) constituting the measurement stage MST. An X-axis movable element (not shown) made of a magnetic pole unit is provided inside the opening of the measurement stage main body 92. That is, the X-axis stator 80 and the X-axis mover constitute a moving magnet type X-axis linear motor that drives the measurement stage MST in the X-axis direction. Hereinafter, this X-axis linear motor will be appropriately referred to as an X-axis linear motor 80 using the same reference numerals as those of the X-axis stator 80 that is the stator.

  In the present embodiment, the stage drive unit 124 shown in FIG. 6 is configured by the Y-axis linear motors 82 to 85, the X-axis linear motors 80 and 81, and the Z / tilt drive mechanisms of the wafer stage WST and the measurement stage MST. Has been. Each of the linear motors constituting the stage driving unit 124 is controlled by the main controller 20 shown in FIG.

  The positions of wafer stage WST and measurement stage MST configured as described above are, for example, 0 by interferometer system 118 in FIG. 6 via the side surfaces (mirror-finished surfaces) of wafer table WTB and measurement table MTB. It is always detected with a resolution of about 5 to 1 nm. The interferometer system 118 includes the Y interferometer 16 for detecting the position of the wafer stage WST in the Y-axis direction shown in FIG. 2 and the Y interferometer 18 for detecting the position of the measurement stage MST in the Y-axis direction. , A plurality of X interferometers for detecting the position of each stage in the X-axis direction, the position of the wafer table WTB in the Z-axis direction (the θx direction (the rotation direction around the X axis), and the θy direction (the rotation direction around the Y axis) And a Z interferometer for measuring (including the position of). The measurement value of the interferometer system 118 is sent to the main controller 20, and the main controller 20 uses the measurement value of the interferometer system 118 via the stage drive unit 124 in the X-axis direction of each stage WST and MST. , The position (and speed) in the Y-axis direction and the θz direction (rotation direction around the Z axis), and the position in the Z-axis direction (θx direction (rotation direction around the X axis) and θy direction (around the Y axis) of the wafer table WTB. (Including the rotation direction) position). In addition, it is good also as providing a movable mirror in each table instead of carrying out the mirror surface process of each table.

  In addition, it is good also as detecting the position of each stage with a linear encoder etc. with the measurement by an interferometer system instead of this.

  Although not shown in FIG. 3 and the like, actually, a frame-shaped counter mass is provided so as to surround the base board 112 and the Y-axis stators 86 and 87. This counter mass is levitated and supported on the floor surface F by, for example, a vacuum preload type gas hydrostatic bearing, and receives a reaction force caused by movement of the wafer stage WST and the measurement stage MST in the XY two-dimensional plane so as to freely move. It has become. The counter mass is provided with a trim motor TM (not shown in FIG. 3, refer to FIG. 6) composed of a voice coil motor or the like for positioning the counter mass. The trim motor TM is driven and controlled by the main controller 20 based on counter mass position information detected by a sensor (not shown).

  Furthermore, in the exposure apparatus main body 10A of the present embodiment, although not shown in FIG. 2 and the like, the exposure apparatus main body 10A includes an irradiation system 90a and a light receiving system 90b (see FIG. 6) attached to a holding member that holds the projection unit PU. An oblique incidence type multi-point focal position detection system similar to that disclosed in JP-A-6-283403 (corresponding to US Pat. No. 5,448,332) is provided.

  Next, a motor cooling system included in the exposure apparatus main body 10A in the present embodiment will be described with reference to FIG. FIG. 4 shows a simplified configuration of the cooling system 110 of the present embodiment.

  As is clear from FIG. 4, the cooling system 110 shown in FIG. 4 uses pure water from a tank 41 that can store a predetermined amount of pure water to the motor armature units (11, 86, 87, 81, 80). , TM) is a circulation system for supplying pure water to the tank 41 after cooling them and cooling them.

  The cooling system 110 includes the tank 41, a pump 43, a cooling device 45, a specific resistance value detection sensor SR, heaters 47a to 47e, a flow control valve 49, a deminer 51, a piping system, and the like.

  One end of a water supply pipe 26 is connected to the tank 41. The other end of the water supply pipe 26 is connected to an ultrapure water production apparatus (not shown) for producing ultrapure water installed in the factory. Further, the tank 41 has one end portion and the other end portion of the circulation main passage 28 that circulates pure water (however, the other end portion side is branched into a first conduit 28a and a second conduit 28b described later) Is connected). From the water supply pipe 26, ultrapure water having a flow rate of about 1 to 10% (for example, 1 L / min) of the flow rate of water flowing through the circulation main line 28 (for example, an arbitrary flow rate in 70 to 80 L / min) is obtained. It is always supplied.

  The cooling device 45 includes a cooler, a temperature sensor that detects the temperature of pure water, and a controller that controls the cooler so that the temperature of pure water becomes a predetermined temperature according to the detection result of the temperature sensor. Has been.

  The specific resistance value detection sensor SR detects the specific resistance value of the pure water that has passed through the cooling device 45 and outputs it to the main control device 20 of FIG. The circulation main path 28 branches into five branch paths after passing the specific resistance detection sensor SR.

  The heaters 47a to 47e are provided in each of the branch paths. Each heater has a built-in temperature sensor that heats the pure water that passes through each branch path based on the detected value of the temperature sensor and adjusts the temperature to the temperature required to control the temperature of the armature unit of each motor. To do. Each branch path is connected to a heat generating portion of each motor, that is, a housing of an armature unit constituting a linear motor and a voice coil motor, and pure water is directly supplied into each housing. That is, the housing of each motor constitutes a part of the branch path.

  Each of the five branch paths merges to become one circulation trunk path again through the armature unit housing of each motor. The circulation main path 28 is then branched into two (herein referred to as the first pipe line 28a and the second pipe line 28b), and the end portion of each pipe line opposite to the branch line is the tank 41 described above. It is connected to the.

  The flow control valve 49 is composed of a valve capable of adjusting the opening thereof, and is provided in the middle of the second pipe line 28b. By adjusting the opening degree of the flow control valve 49, it is possible to set the flow rate of water flowing through the circulation main path 28 and the flow rate of water flowing through the second pipe line 28b. That is, the flow rate control valve 49 can change the ratio of the flow rate of water flowing through the first pipe line 28a and the second pipe line 28b. The flow rate control valve 49 can set the flow rate of water flowing to the deminer 51 between 10 and 50 L / min, and is set to 50 L / min as an example in the present embodiment.

The ion removing device (deminer) 51 is provided in the middle of the second pipe line 28b, and contains an ion exchange resin therein, thereby removing ions (for example, Na ⁺ , Cl ⁻ ions) in pure water.

  Here, the specific resistance value of pure water after passing through the deminer 51 is approximately 18 (MΩ · cm) close to the theoretical pure water, but the specific resistance value required for cooling the motor is For example, since it is about 10 (MΩ · cm), it is not necessary to pass all of the pure water passing through the circulation main path 28 through the deminer 51 as described above. It should be noted that the flow rate of water flowing through the deminer 51 by the flow rate control valve 49 is not necessarily set to a fixed value.

  That is, in the present embodiment, the pure water passing through the first conduit 28a and the pure water passing through the second conduit 28b merge to form the armature unit (11, 86, 87, 81, 80, TM) of each motor. The main controller 20 feedback-controls the opening degree of the flow control valve 49 based on the value of the specific resistance value detection sensor SR so that the specific resistance value at the stage of supply to 10 becomes (MΩ · cm). May be. Specifically, the specific resistance value of pure water in a state where the opening degree of the flow control valve 49 is set to a predetermined opening degree is detected by the specific resistance value detection sensor SR, and if the detected value is 10 (MΩ · cm) or less. For example, by increasing the opening degree of the flow control valve 49, more pure water is passed through the deminer 51 so that the detected value is about 10 (MΩ · cm), and the detected value is 10 (MΩ · cm). If it is above, by decreasing the opening degree of the flow control valve 49, a smaller amount of pure water is passed through the deminer 51 so that the detected value becomes about 10 (MΩ · cm).

  By doing in this way, compared with the case where all the pure water is passed through the deminer 51, the amount of pure water passing through the deminer 51 can be reduced, so that the amount of ion exchange resin to be built in the deminer 51 is reduced. Thus, the deminer 51 can be reduced in size. Since the deminer 51 thus miniaturized can be arranged close to the same floor surface as the exposure apparatus main body 10A, the distance of the piping such as the circulation main path 28 can be shortened, and the metal piping can be used for the piping. Even if it is used, it is possible to suppress a decrease in the specific resistance value of pure water due to elution of ions in the metal pipe.

  By the way, the circulation main path 28 further includes a branch path 28c that branches between the pump 43 and the cooling device 45, and a branch path 28d that branches between the cooling device 45 and the specific resistance detection sensor SR. have.

  The branch path 28c is connected to a tank that constitutes a circulation system that circulates water (hereinafter referred to as “circulation water”) that regulates the temperature of an optical system such as the projection unit PU, which is called a fine system. Therefore, the pure water branched by the branch path 28c is mixed with the circulating water. For this reason, since the circulating water can always be replaced with pure water, it is possible to maintain a long life of the O-ring or packing of resin or the like used in the projection unit PU without being affected by chlorine or the like. ing.

  The branch path 28d is connected to the liquid supply device 5 for supplying water used for the liquid immersion described above. The pure water supplied to the liquid supply device 5 is supplied at a predetermined temperature (water used for immersion (between the front lens 191 and the wafer W) by a temperature control device provided in the liquid supply device 5. After the temperature is adjusted to the optimum temperature for adjusting the temperature of water), it flows in the jacket 73 shown in FIG. A supply pipe 77 provided at the tip of the liquid supply nozzle 31A of FIG. 2 is inserted into the jacket 73, and the temperature of the water is controlled while water used for immersion passes through the supply pipe 77. The temperature is adjusted to almost the same temperature as pure water. As the supply pipe 77, for example, a resin having excellent corrosion resistance such as PFA (perfluoroalkoxyethylene) is used.

  In addition, the sum total of the flow volume of the pure water which passes the branch path 28c and the branch path 28d is about 1 to 10% (for example, 1 L / min) of the flow volume (for example, 70-80 L / min) of the water which flows through the circulation trunk path 28. That is, the flow rate can be almost the same as the amount of pure water supplied from the supply pipe 26.

  FIG. 6 shows the main configuration of the control system of the exposure apparatus 10. This control system is mainly configured of a main control device 20 composed of a microcomputer (or a workstation) for overall control of the entire apparatus. The main controller 20 is connected to a display device 95 composed of a CRT monitor, a liquid crystal monitor or the like.

  Next, the processing operation in the substrate processing system 100 of the present embodiment will be described focusing on the exposure operation in the exposure apparatus main body 10A. FIG. 3 shows a state in which step-and-scan exposure is performed on a wafer (final wafer in a lot) W on wafer stage WST. At this time, measurement stage MST stands by at a predetermined standby position where it does not collide with wafer stage WST.

  The above exposure operation is performed based on the result of wafer alignment such as enhanced global alignment (EGA) performed in advance by the main controller 20 and the measurement result of the baseline of the latest alignment system ALG. Wafer stage WST is moved to a scanning start position (acceleration start position) for exposure of each shot area on W, and a pattern formed on reticle R for each shot area is transferred by a scanning exposure method. This is performed by repeating the scanning exposure operation. The above exposure operation is performed with water held between the front lens 191 and the wafer W.

  Then, at the stage where the exposure to wafer W is completed on wafer stage WST side, main controller 20 controls stage drive unit 124 based on the measurement value of interferometer system 118 to provide wafer stage WST (wafer table WTB). ) Is retracted from directly below the projection unit PU, and the measurement stage MST (measurement table MTB) is moved to just below the projection unit PU.

  In this movement, water between the front lens 191 and the wafer W may be collected, and each stage may be moved after the collection, or the wafer stage WST and the measurement stage MST are brought close to or in contact with each other. In this state, the water may be moved so as to be transferred from the wafer stage WST side to the measurement stage MST side.

  Next, main controller 20 controls stage drive unit 124 based on the measurement value of interferometer system 118 to move the position of wafer stage WST to a predetermined wafer exchange position and move the wafer stage WST to the next lot. Exchange to the first wafer. In this case, the wafer is a wafer coated with a photosensitive agent in the coater in the C / D 12 of FIG. 1, and is transferred into the exposure apparatus main body 10A via the interface unit 14 and the loader. On the other hand, the wafer that has been exposed is transferred into the C / D 12 via the loader and the interface unit 14, and a developing process is performed in the developer in the C / D 12.

  In parallel with the wafer exchange, predetermined measurement using the measurement stage MST is performed as necessary. An example of the predetermined measurement in this case is baseline measurement of the alignment system ALG.

  Then, at the stage where the above-described operations on both stages WST and MST are completed, main controller 20 controls stage drive unit 124 based on the measurement value of interferometer system 118 to measure measurement stage MST (measurement table MTB). ) Is retracted from directly below the projection unit PU, and the wafer stage WST (wafer table WTB) is moved to just below the projection unit PU.

  Thereafter, main controller 20 performs wafer alignment and step-and-scan exposure operations on a new wafer, and sequentially transfers the reticle pattern to a plurality of shot areas on the wafer. Thereafter, the same operation is repeated.

  In the above description, the case where the baseline measurement is performed as the measurement operation has been described. However, the present invention is not limited to this, and the measuring instrument group of the measurement stage MST is exchanged while each wafer is exchanged on the wafer stage WST side. May be used to perform at least one of illuminance measurement, illuminance unevenness measurement, aerial image measurement, wavefront aberration measurement, and the like, and reflect the measurement result on the subsequent wafer exposure. Specifically, for example, the projection optical system PL can be adjusted by an imaging characteristic correction controller (not shown) based on the measurement result.

  By the way, in the main controller 20, the ion exchange resin in the deminer 51 is based on the detection value of the sensor 101 (not shown in FIG. 4, see FIG. 6) that detects the specific resistance value of pure water immediately before entering the deminer 51. Is output to the display device 95. In this case, the lifetime of the deminer 51 is predicted as follows.

  FIG. 7 shows the specific resistance value of pure water at the inlet of the deminer 51 and ion exchange in the deminer 51 when pure water having a predetermined temperature (for example, 25 ° C.) and a predetermined amount (50 liters per minute) is passed through the deminer 51. It is a graph which shows the relationship with the lifetime of resin. This graph can be obtained, for example, by performing experiments or simulations. As shown in this graph, for example, when the specific resistance value at the entrance of the deminer is maintained at about 7.7 (MΩ · cm) at the start of use, the service life is reached after about 180 days from the start of use. For example, when the specific resistance value at the entrance of the deminer is maintained at about 2.0 (MΩ · cm) at the start of use, it can be predicted that the life will be reached after about 30 days from the start of use. It is like that. This relationship shows that when the amount of water doubles, the amount of ions in pure water doubles. For example, if the specific resistance value is about 7.7 (MΩ · cm), about 90 days from the start of use. If the lifetime is reached later and the specific resistance value is about 2.0 (MΩ · cm), the lifetime is reached about 15 days after the start of use.

  In practice, since the specific resistance value is not constant, main controller 20 predicts the lifetime of the ion exchange resin using a conversion formula based on the graph of FIG. 7 according to the change in specific resistance value. The information is displayed on the display device 95 to notify an operator or the like.

  As described above in detail, according to the exposure apparatus of the present embodiment, the circulation main path 28 for supplying water to the armature units (11, 86, 87, 81, 80, TM) of the motor in the exposure apparatus main body 10A. And a branch path 28c, 28d for supplying a part of pure water to a part different from the motor of the exposure apparatus main body, the fine system including the projection unit PU and the temperature control of water used for immersion It is possible to control the temperature with water from which ions have been removed. Thereby, by cooling the armature unit of the motor, the temperature change by the motor in the vicinity of wafer stage WST, measurement stage MST, and reticle stage RST can be prevented, and fluctuations of the interferometer and the like can be suppressed. The detection accuracy and the stage movement accuracy can be improved, and pure water from which ions have been removed by the deminer 51 is supplied to the motor, so that the problem of insulation due to water does not occur. As for the projection unit PU, the temperature of the projection unit PU can be controlled, and the O-ring, packing, etc. used in the projection unit PU can have a long life. Furthermore, by controlling the temperature of water used for immersion using pure water, metal ions are prevented from leaching into the water unlike when using a heater to adjust the temperature of immersion water. It becomes possible to do.

  Moreover, in the said embodiment, the pure water which does not pass a deminer, and the pure water which passes a deminer are branched by the 1st pipe line 28a and the 2nd pipe line 28b, and the flow volume of the pure water which flows through each pipe line is controlled by the flow control valve 49. Therefore, it is possible to set the specific resistance value of pure water obtained after merging to a desired value. Further, since the amount of water passing through the deminer can be reduced, the ion exchange resin contained in the deminer can be reduced in size, and thus the deminer can be reduced in size.

  Further, according to the exposure apparatus of the present embodiment, since the exposure apparatus main body 10A and the deminer 51 are arranged close to each other, the length of the conduit from the deminer 51 to each motor can be shortened. In this case, even if a metal pipe or the like is used for the pipe line, since ions are hardly eluted from the metal pipe into the pure water, pure water having a high specific resistance value can be supplied to each motor. In addition, since the deminer is reduced in size as described above, the footprint of the entire exposure apparatus can be reduced.

  Further, according to the exposure apparatus of the present embodiment, the specific resistance value of water passing through the deminer 51 is detected by the sensor 101, and the lifetime of the ion exchange resin in the deminer 51 is predicted based on the detection result. By exchanging the ion exchange resin before reaching, water containing a large amount of ions can be prevented from being supplied to the armature unit of each motor.

  Moreover, in the said embodiment, since the water of the flow volume about 1 to 10% of the flow volume of the water which circulates through the circulation trunk line 28 is always supplied, it is possible to always maintain water quality high.

  In the above embodiment, the cooling system is a circulation system, and the temperature control device (cooling device 45 and heaters 47a to 47e) is provided in the circulation system. However, the present invention is limited to this. For example, it may have a supply pipe connecting the pure water tank to each motor, and a part of the supply pipe may be branched to control the temperature of the water used for the fine system and immersion. . In this case, pure water whose temperature is adjusted externally may be supplied to each motor.

  In the above embodiment, the case where the branch paths 28c and 28d are branched on the upstream side of each motor has been described. However, the present invention is not limited to this, and the branch paths 28c and 28d may be branched on the downstream side of each motor. good.

  In the above embodiment, the flow rate of pure water flowing through the first pipe line 28a and the second pipe line 28b is set by the flow rate control valve 49, but the flow rate control valve is located in the middle of the second pipe line 28b. It is good also as providing not only in the middle of the 1st pipe line 28a. Moreover, it is good also as providing the flow volume adjustment valve which can adjust the ratio of the flow volume of the pure water which flows through each pipe line in the part into which the 1st, 2nd pipe lines 28a and 28b branch.

  In addition, for example, in order to change the flow rate of pure water passing through the branch path 28 c, a flow control valve is provided in the middle of the branch path 28 c or in a part of the circulation main path 28 between the branch path 28 c and the cooling device 45. Alternatively, a flow rate adjusting valve capable of adjusting the ratio of the flow rate of pure water flowing through each path may be provided at a portion where the circulation line 28 and the branch path 28c branch. In addition, for example, in order to change the flow rate of pure water passing through the branch path 28d, a flow control valve is provided in the middle of the branch path 28d or in a part of the circulation main path 28 between the branch path 28d and the sensor SR. Alternatively, a flow rate adjusting valve capable of adjusting the ratio of the flow rate of pure water flowing through each path may be provided at a portion where the circulation line 28 and the branch path 28d branch.

  In the above embodiment, the case where the opening degree of the flow control valve 49 is adjusted based on the specific resistance value of pure water has been described. However, the present invention is not limited to this, and pure water (25 ° C.) Since there is a relationship as shown in FIG. 8 between the specific resistance value and the ion concentration (ppb), the opening degree of the flow control valve 49 is adjusted based on the ion concentration of pure water. Also good.

  In the above embodiment, the lifetime of the ion exchange resin is predicted based on the specific resistance value of pure water at the inlet of the deminer 51. However, the present invention is not limited to this, and it is similar to the adjustment of the opening degree of the flow control valve 49. The lifetime of the ion exchange resin may be predicted based on the ion concentration. In this case, it is possible to predict the lifetime of the ion exchange resin from the ion concentration based on the graph of FIG. 9 derived from the relationship of FIG. 7 and the relationship of FIG.

  In the above embodiment, the case where the wafer stage apparatus 50 includes the measurement stage MST has been described. However, the measurement stage MST may not be provided. In this case, a measurement device or the like provided in measurement stage MST may be provided on wafer stage WST.

  In addition, when the cooling system 110 of the above-described embodiment is used for cooling a linear motor that drives the reticle stage RST, the cooling system may be provided independently for the wafer stage device 50 and the reticle stage RST. Further, the driving part of the reticle blind that sets the illumination area of the reticle R may be cooled using a branch path.

  In the above-described embodiment, the case where the present invention is applied to the immersion exposure apparatus has been described. However, the present invention is not limited to this, and can of course be adopted in a normal stepper or the like. In this case, the water that has passed through the branch path 28d may be used for temperature control of portions other than the motor of the exposure apparatus main body 10A, or the branch path 28d may not be provided.

In the above-described embodiment, the case where the pure water that passes through the deminer 51 and the pure water that does not pass through the deminer 51 are branched at the first and second pipes 28a and 28b has been described. All pure water may be passed through.

  In addition, although the said embodiment demonstrated the case where the armature unit of five motors was cooled with a pure water, this invention is not restricted to this, If pure water is supplied to at least one of these, good.

  In the above embodiment, the case where the counter mass is provided in the wafer stage apparatus has been described. However, the present invention is not limited to this, and the counter mass may be provided on the reticle stage side. When a trim motor that moves the counter mass on the side is provided, the trim motor may be cooled by the cooling system 110 of this embodiment. Further, the counter mass may not be provided in any stage device.

  In the above-described embodiment, the case where the reduction system is used as the projection optical system PL has been described. However, the projection optical system may be either a unity magnification system or an enlargement system. Further, a so-called catadioptric system (catadioptric system) or a reflective system composed only of a reflective optical element may be used.

  In the above-described embodiment, the case where the present invention is applied to an exposure apparatus for manufacturing a semiconductor has been described. However, the present invention is not limited to this, and for example, exposure for liquid crystal that transfers a liquid crystal display element pattern onto a square glass plate. The present invention can be widely applied to an apparatus, an exposure apparatus for manufacturing a thin film magnetic head, an image sensor, an organic EL, a micromachine, a DNA chip, and the like.

  Further, in order to manufacture reticles or masks used in not only microdevices such as semiconductor elements but also light exposure apparatuses, EUV exposure apparatuses, X-ray exposure apparatuses, electron beam exposure apparatuses, etc., glass substrates or silicon wafers, etc. The present invention can also be applied to an exposure apparatus that transfers a circuit pattern.

  As described above, the exposure apparatus of the present invention is suitable for exposing a substrate.

1 is a schematic view showing a substrate processing system according to an embodiment. It is a figure which shows the exposure apparatus main body of FIG. It is a top view which shows the stage apparatus of FIG. It is a figure which shows the cooling system of one Embodiment. It is a perspective view which shows the pipe and jacket in a liquid supply apparatus partially in cross section. It is a block diagram which shows the main structures of the control system of exposure apparatus. It is a graph which shows the relationship between the specific resistance value of the pure water in a deminer inlet, and the lifetime of an ion exchange resin. It is a graph which shows the relationship between the specific resistance value of pure water, and ion concentration. It is a graph which shows the relationship between the ion concentration of pure water in a deminer inlet, and the lifetime of an ion exchange resin.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10A ... Exposure apparatus main body, 11 ... Reticle stage drive part (drive device), 20 ... Main control apparatus (prediction apparatus), 28 ... Circulation pipe line (1st supply path), 28a ... 1st pipe line (2nd supply path) ), 28c ... Branch path (second supply path), 28d ... Branch path (second supply path), 51 ... Deminer (ion removal device), 81, 80 ... X-axis stator (drive device), 86, 87 ... Y axis stator (drive device), 101 ... sensor (detector), F ... floor surface, TM ... trim motor (drive device), W ... wafer (substrate).

Claims (7)

An exposure apparatus body including a projection optical system that projects a pattern onto a substrate, and a liquid supply device that supplies a liquid between the projection optical system and the substrate via a resinous supply tube;
A first supply path for supplying water to a driving device in the exposure apparatus body;
An ion removing device that passes at least a part of the water supplied to the driving device via the first supply path and removes ions from the passing water ;
A second supply that branches from the first supply path upstream or downstream of the drive unit and supplies a part of the water flowing in the first supply path to a part of the exposure apparatus main body different from the drive unit. The road;
A first temperature control for adjusting the temperature of the liquid supplied between the projection optical system and the substrate through the resin supply pipe by heat exchange with the water supplied from the second supply path. And an exposure apparatus.   The exposure apparatus according to claim 1, further comprising a second temperature control device that controls the temperature of the water.   The exposure apparatus according to claim 1, wherein the water supplied to the second supply path is water that has passed through the driving device.   The apparatus according to claim 1, further comprising a setting device that sets a ratio between a flow rate of the water supplied to the first supply path and a flow rate of the water supplied to the second supply path. The exposure apparatus according to any one of the above. The first supply path is a circulation-type supply path;
5. The apparatus according to claim 1, further comprising a third supply path that supplies water having a specific resistance value higher than that of the water circulating through the first supply path to the first supply path. The exposure apparatus described.   One end of the third supply path is connected to the tank for storing the water, the other end is connected to the first supply path, and the flow rate is about 1 to 10% of the flow rate of the water circulating through the first supply path. The exposure apparatus according to claim 5, wherein the water is supplied to the first supply path. The exposure apparatus main body has a projection optical system that projects a pattern onto the substrate,
The exposure apparatus according to claim 1, wherein water from the second supply path is supplied to the projection optical system.

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